In the late seventeenth and early eighteenth centuries, Locke's Two Treatises were not frequently cited. The historian Julian Hoppit has claimed that the book, "except among some Whigs, even as a contribution to the intense debate of the 1690s it made little impression and was generally ignored until 1703 (though in Oxford in 1695 it was reported to have made 'a great noise')". John Kenyon in his study of British political debate from 1689 to 1720, has remarked that Locke's theories were "mentioned so rarely in the early stages of the [Glorious] Revolution, up to 1692, and even less thereafter, unless it was to heap abuse on them" and that "no one, including most Whigs, [were] ready for the idea of a notional or abstract contract of the kind adumbrated by Locke". In contrast, Kenyon adds that Algernon Sidney's Discourses Concerning Government were "certainly much more influential than Locke's Two Treatises".
In the fifty years after Queen Anne's death in 1714, the Two Treatises were reprinted only once (apart from in the collected works of Locke). However with the rise of American resistance to British attempts to tax them, the Second Treatise gained a new readership; it was frequently cited in the debates in both America and Britain. The first American printing occurred in 1773 in Boston.
Locke exercised a profound influence on political philosophy, in particular on modern liberalism. Michael Zuckert has argued that Locke launched liberalism by tempering Hobbesian absolutism and clearly separating the realms of Church and State. He had a strong influence on Voltaire who called him "le sage Locke". His arguments concerning liberty and the social contract later influenced the written works of Alexander Hamilton, James Madison, Thomas Jefferson, and other Founding Fathers of the United States. In fact, one passage from the Second Treatise is reproduced verbatim in the Declaration of Independence, the reference to a "long train of abuses." Such was Locke's influence that Thomas Jefferson wrote: "Bacon, Locke and Newton... I consider them as the three greatest men that have ever lived, without any exception, and as having laid the foundation of those superstructures which have been raised in the Physical and Moral sciences". Today, most contemporary libertarians claim Locke as an influence.
But Locke's influence may have been even more profound in the realm of epistemology. Locke redefined subjectivity, or self, and intellectual historians such as Charles Taylor and Jerrold Seigel argue that Locke's An Essay Concerning Human Understanding (1690) marks the beginning of the modern Western conception of the self.
Theories of religious tolerance
Locke, writing his Letters Concerning Toleration (1689–92) in the aftermath of the European wars of religion, formulated a classic reasoning for religious tolerance. Three arguments are central: (1) Earthly judges, the state in particular, and human beings generally, cannot dependably evaluate the truth-claims of competing religious standpoints; (2) Even if they could, enforcing a single "true religion" would not have the desired effect, because belief cannot be compelled by violence; (3) Coercing religious uniformity would lead to more social disorder than allowing diversity.
With regard to his position on religious tolerance, Locke was influenced by Baptist theologians like John Smyth and Thomas Helwys, who had published tracts demanding freedom of conscience in the early seventeenth century. Baptist theologian Roger Williams founded the colony Rhode Island in 1636, where he combined a democratic constitution with unlimited religious freedom. His tract The Bloody Tenent of Persecution for Cause of Conscience (1644), which was widely read in the mother country, was a passionate plea for absolute religious freedom and the total separation of church and state. Freedom of conscience had had high priority on the theological, philosophical and political agenda, since Martin Luther refused to recant his beliefs before the Diet of the Holy Roman Empire at Worms in 1521, unless he would be proved false by the Bible. Locke was part of this Protestant tradition. He was also influenced by the liberal ideas of Presbyterian politician and famous poet John Milton, who was a staunch advocate of freedom in all its forms. As assistant to Oliver Cromwell, Milton took part in drafting a constitution of the Independents (Agreement of the People; 1647) that strongly stressed the equality of all humans as a consequence of democratic tendencies.
Constitution of Carolina
Appraisals of Locke have often been tied to appraisals of liberalism in general, and also to appraisals of the United States. Detractors note that (in 1671) he was a major investor in the English slave-trade through the Royal African Company. In addition, he participated in drafting the Fundamental Constitutions of Carolina while Shaftesbury's secretary, which established a feudal aristocracy and gave a master absolute power over his slaves. For example, Martin Cohen notes that Locke, as a secretary to the Council of Trade and Plantations (1673–4) and a member of the Board of Trade (1696–1700), was in fact, "one of just half a dozen men who created and supervised both the colonies and their iniquitous systems of servitude". Some see his statements on unenclosed property as having been intended to justify the displacement of the Native Americans. Because of his opposition to aristocracy and slavery in his major writings, he is accused of hypocrisy and racism, or of caring only for the liberty of English capitalists.
Theory of value and property
Locke uses the word property in both broad and narrow senses. In a broad sense, it covers a wide range of human interests and aspirations; more narrowly, it refers to material goods. He argues that property is a natural right and it is derived from labour.
In Chapter V of his Second Treatise, Locke argues that the individual ownership of goods and property is justified by the labour exerted to produce those goods or utilise property to produce goods beneficial to human society.
Locke stated his belief, in his Second Treatise, that nature on its own provides little of value to society; he provides the implication that the labour expended in the creation of goods gives them their value. This is used as supporting evidence for the interpretation of Locke's labour theory of property as a labour theory of value, in his implication that goods produced by nature are of little value, unless combined with labour in their production and that labour is what gives goods their value.
Locke believed that ownership of property is created by the application of labour. In addition, he believed property precedes government and government cannot "dispose of the estates of the subjects arbitrarily." Karl Marx later critiqued Locke's theory of property in his own social theory.
Locke's political theory was founded on social contract theory. Unlike Thomas Hobbes, Locke believed that human nature is characterised by reason and tolerance. Like Hobbes, Locke believed that human nature allowed men to be selfish. This is apparent with the introduction of currency. In a natural state all people were equal and independent, and everyone had a natural right to defend his “Life, health, Liberty, or Possessions". Most scholars trace the phrase "life, liberty, and the pursuit of happiness," in the American Declaration of Independence, to Locke's theory of rights, though other origins have been suggested.
Like Hobbes, Locke assumed that the sole right to defend in the state of nature was not enough, so people established a civil society to resolve conflicts in a civil way with help from government in a state of society. However, Locke never refers to Hobbes by name and may instead have been responding to other writers of the day. Locke also advocated governmental separation of powers and believed that revolution is not only a right but an obligation in some circumstances. These ideas would come to have profound influence on the Declaration of Independence and the Constitution of the United States.
Limits to accumulation
According to Locke, unused property is waste and an offence against nature, but, with the introduction of “durable” goods, men could exchange their excessive perishable goods for goods that would last longer and thus not offend the natural law. In his view, the introduction of money marks the culmination of this process, making possible the unlimited accumulation of property without causing waste through spoilage. He also includes gold or silver as money because they may be “hoarded up without injury to anyone,” since they do not spoil or decay in the hands of the possessor. In his view, the introduction of money eliminates the limits of accumulation. Locke stresses that inequality has come about by tacit agreement on the use of money, not by the social contract establishing civil society or the law of land regulating property. Locke is aware of a problem posed by unlimited accumulation but does not consider it his task. He just implies that government would function to moderate the conflict between the unlimited accumulation of property and a more nearly equal distribution of wealth; he does not identify which principles that government should apply to solve this problem. However, not all elements of his thought form a consistent whole. For example, labour theory of value of the Two Treatises of Government stands side by side with the demand-and-supply theory developed in a letter he wrote titled Some Considerations on the Consequences of the Lowering of Interest and the Raising of the Value of Money. Moreover, Locke anchors property in labour but in the end upholds the unlimited accumulation of wealth.
On price theory
Locke’s general theory of value and price is a supply and demand theory, which was set out in a letter to a Member of Parliament in 1691, titled Some Considerations on the Consequences of the Lowering of Interest and the Raising of the Value of Money. He refers to supply as "quantity" and demand as "rent". "The price of any commodity rises or falls by the proportion of the number of buyer and sellers," and "that which regulates the price... [of goods] is nothing else but their quantity in proportion to their rent." The quantity theory of money forms a special case of this general theory. His idea is based on "money answers all things" (Ecclesiastes) or "rent of money is always sufficient, or more than enough," and "varies very little..." Locke concludes that as far as money is concerned, the demand is exclusively regulated by its quantity, regardless of whether the demand for money is unlimited or constant. He also investigates the determinants of demand and supply. For supply, he explains the value of goods as based on their scarcity and ability to be exchanged and consumed. He explains demand for goods as based on their ability to yield a flow of income. Locke develops an early theory of capitalisation, such as land, which has value because "by its constant production of saleable commodities it brings in a certain yearly income." He considers the demand for money as almost the same as demand for goods or land; it depends on whether money is wanted as medium of exchange or as loanable funds. As a medium of exchange, he states that "money is capable by exchange to procure us the necessaries or conveniences of life," and for loanable funds, "it comes to be of the same nature with land by yielding a certain yearly income... or interest."
Locke distinguishes two functions of money, as a "counter" to measure value, and as a "pledge" to lay claim to goods. He believes that silver and gold, as opposed to paper money, are the appropriate currency for international transactions. Silver and gold, he says, are treated to have equal value by all of humanity and can thus be treated as a pledge by anyone, while the value of paper money is only valid under the government which issues it.
Locke argues that a country should seek a favourable balance of trade, lest it fall behind other countries and suffer a loss in its trade. Since the world money stock grows constantly, a country must constantly seek to enlarge its own stock. Locke develops his theory of foreign exchanges, in addition to commodity movements, there are also movements in country stock of money, and movements of capital determine exchange rates. He considers the latter less significant and less volatile than commodity movements. As for a country’s money stock, if it is large relative to that of other countries, he says it will cause the country’s exchange to rise above par, as an export balance would do.
He also prepares estimates of the cash requirements for different economic groups (landholders, labourers and brokers). In each group he posits that the cash requirements are closely related to the length of the pay period. He argues the brokers – middlemen – whose activities enlarge the monetary circuit and whose profits eat into the earnings of labourers and landholders, have a negative influence on both personal and the public economy to which they supposedly contribute.
Locke defines the self as "that conscious thinking thing, (whatever substance, made up of whether spiritual, or material, simple, or compounded, it matters not) which is sensible, or conscious of pleasure and pain, capable of happiness or misery, and so is concerned for itself, as far as that consciousness extends". He does not, however, ignore "substance", writing that "the body too goes to the making the man."
In his Essay, Locke explains the gradual unfolding of this conscious mind. Arguing against both the Augustinian view of man as originally sinful and the Cartesian position, which holds that man innately knows basic logical propositions, Locke posits an "empty" mind, a tabula rasa, which is shaped by experience; sensations and reflections being the two sources of all our ideas.
Locke's Some Thoughts Concerning Education is an outline on how to educate this mind: he expresses the belief that education maketh the man, or, more fundamentally, that the mind is an "empty cabinet", with the statement, "I think I may say that of all the men we meet with, nine parts of ten are what they are, good or evil, useful or not, by their education."
Locke also wrote that "the little and almost insensible impressions on our tender infancies have very important and lasting consequences." He argued that the "associations of ideas" that one makes when young are more important than those made later because they are the foundation of the self: they are, put differently, what first mark the tabula rasa. In his Essay, in which both these concepts are introduced, Locke warns against, for example, letting "a foolish maid" convince a child that "goblins and sprites" are associated with the night for "darkness shall ever afterwards bring with it those frightful ideas, and they shall be so joined, that he can no more bear the one than the other."
"Associationism", as this theory would come to be called, exerted a powerful influence over eighteenth-century thought, particularly educational theory, as nearly every educational writer warned parents not to allow their children to develop negative associations. It also led to the development of psychology and other new disciplines with David Hartley's attempt to discover a biological mechanism for associationism in his Observations on Man (1749).